Resistor



Oct. 31, 1944. J, J` KOPPLE 2,361,405

RESISTOR Filed July '7, 1942 l N V EN TOR.

dbf/Af I KOPP/5 BY Patented oci. 31, 1944 UNITEDv STATES PATENT .oFEicEBESISTOB John J. xoppie, Brooklyn, N. Y.. minor to The Ohio CarbonCompany, Cleveland, Ohio, a corporation of -Ohio Application July 7,1.942, Serial No. 449,974

(Cl. SG1-6 3) 4 Claim..

This invention .relates to resistance elements and particularly thosewhich are used in the electronic field, particularly in connection withradio, signal or television equipment.

An object of the invention is to provide a shield for the resistor so asto minimize interference in the operation of electronic equipment. SDelciilcally, the invention includes as an object the provision of meansfor so shielding the resistor connection thereto..

In the drawing, Fig. 1 is a side elevation, partly in section, of aresistor unit embodying my invention: Fig. 2 is a section taken on theline 2--2 in Fig.. 1; and Fig. 3 is a side elevation, partly in section.of a modified form of resistor unit.

The resistance element with which the present invention is shownembodies a bar of resistance material i0, preferably round in form, fromthe ends of which project current conducting leads Il. In the form shownin Fig. 1, each lead is electrically connected to the body through themedium of acup-shaped member i4 'of electroconductive material which isattached to each end of the body. Each member is positioned on the bodywith the open end thereof facing-the other and each open end may engagea band i2 of electro-conductive material, such as copper, which may besprayed onto each end of the resistor body. The closed end of eachmember I4 may be apertured to receive the lead ii, the end of which maybe swaged to the member or otherwise securely attached thereto, as bysoldering. v

The form of shield construction shown in Fig. 1 includes a layer it ofcurrent conductive material which is disposed on theouter surface of anisulating casing I6 that embraces the insulating body and preferablyprojects slightly beyond each end thereof.V Suitable insulating sealingcement may then 4he applied to each end for effecting a moisture proofcap therefor. A

grounded connection 2l may then' be attached to the current conductivematerial iB.

Tit.:l casing i8 may be made of any suitable insulating material, suchas l porcelain. glass, Vresin'ous material, varnished fabric. or anymaterial having suillcient rigidity to withstand handling and retain itstubular shape. yThe current conducting material lli may be copper thatisapplied in the form of 'a spray, or it may be a metallic foil that isrigidly mounted on the outer surface of the casing. l

The ground connection may be made to the layer of conductive material i5in any convenient way, as by soldering thelead 2| directly to the layer,as shown in Fig. 1, or by utilizing a band of current conductivematerial as shown in Fig. 3. The band maycomprise either a layer ofsolder or a metallic sleeve which is pressed A firmly onto the layer i5.Y

A modified form of the construction is shown in Fig. 3,- wherein .thecurrent conducting leads H are embedded within the body of theresistance element, whereby the need for current conductive cup-shapedmembers i4 is obviated. Additionally. the casing maybe molded around theA resistance element and may be made of any insulating resinous plasticmaterial. In such case,

-the ends of the plastic material cover the ends y of the resistanceelement and thereby form an eiiectire moisture-proof seal for the unit.

A shield embodying the present invention may be readily applied toa-resistance element and easily attached to the grounded connection. Theinvention effectively shields the resistor and thereby avoidsobjectionable interference in radio reception, or in any otherelectrical apparatus in which it may be used.

I claim:

-1. In an electrical resistance unit, an electrical resistance element,a current conducting lead electrically connected to and projecting outof the end of each element, an insulating casing enclosing the elementand extending for substan tially thek entire length thereof, and a filmof current conductive material enclosing the outer sur face of thecasing.

2; In an electrical resistance unit, an electrical resistance element, acasing of insulating material embracing the element. a currentconducting lead projecting from each end of the element, a lm of currentconductive material enclosing the exterior surface of said casing. andmeans for sealing each end of the element and casing.

3. In an electrical resistance unit, an electrical resistance elementhaving a. current conducting lead extending from each end thereof, aninsulatingucas'ing' enclosing the element, a film of cover surroundingsaid wall portions and bridging the space therebetween, said insulatingcover intimately engaging said wallfportions to form with saidelectro-conductive member a substantally sealed casing, an electricalresistance element positioned within said casing and connected to saidmembers, a terminal lead attached to each of said electro-conductivemembers, and a illm oi current conducting material enclosing 10 outersurface of said casing.

JOHN J. KOPPLE.

